78855658672529 has 2 divisors, whose sum is σ = 78855658672530. Its totient is φ = 78855658672528.

The previous prime is 78855658672513. The next prime is 78855658672559. The reversal of 78855658672529 is 92527685655887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75171466341904 + 3684192330625 = 8670148^2 + 1919425^2 .

It is a cyclic number.

It is not a de Polignac number, because 78855658672529 - 2⁴ = 78855658672513 is a prime.

It is not a weakly prime, because it can be changed into another prime (78855658672559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39427829336264 + 39427829336265.

It is an arithmetic number, because the mean of its divisors is an integer number (39427829336265).

Almost surely, 2^{78855658672529} is an apocalyptic number.

It is an amenable number.

78855658672529 is a deficient number, since it is larger than the sum of its proper divisors (1).

78855658672529 is an equidigital number, since it uses as much as digits as its factorization.

78855658672529 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20321280000, while the sum is 83.

The spelling of 78855658672529 in words is "seventy-eight trillion, eight hundred fifty-five billion, six hundred fifty-eight million, six hundred seventy-two thousand, five hundred twenty-nine".